Manufacture of starch



March 18, 1930. F. L. JEFFERIES MANUFACTURE OF STARCH Filed Sept. 8, 1928 Patented Mar.l 18, 1930 .Um'rlsn STATES PATENT `ortica FREDERICK-L. JHFERIES, F LA GRANGE, ILLINOIS, A-SSIGNOR T INTERNATIONAL PATENTS DEVELOPMENT COMPANY, 0F WILMINGTON, DELAWARE, A CORPORA- TION 0F DELAWARE w MANUFACTIIRE OF STARCH Applicationvled September 8, 1928. Serial No. 304,687.

This invention rela-tes to the manufacture f of starch from grain, especially Indian corn,

. COI' and is concerned particularly with the part of the process known as the fine slop sepa-` rationin which .line particles of bran and fibre are removed from the starch and gluten magma.

In accordance with methods heretofore employed `the water for use in the .fine slop system which may be either fresh water, or, ac-

ding to later practice, filtrate fromv the starch washing filters, has been heated to certain temperatures in or'der to kfacilitate the draining, of the silk reels and shakers of the fine slop system and to assist in'keeping the entire process heated to the customary temand 110 F. or over a greater range. The

practice, in fact, was adopted many years ago.

vof heating the fresh water used in the ine slo system to temperatures considerably hig er than 110 F., that'is higher than those of the water used in the germ and coarse slop systems'for the v drainage through the silk'reels or shakers of the fine slop system.v The usual practice in this respect has been to heat the water or filtrate atia single point lin advance of the fine slo'p system, that is, in a sin le heater, an'd to va temperature high enoug so that,

taking into account the cooling effect of passing t e liquids throughfthe successive reels or shakers of the line slop system, proper .temperatures will be maintained at the other end of such line slop system, from that at whichthe water enters as well as at the table heads- Apractice of this sort, as applied to a stem re-using waste waters, is disclosed in nited States Patent No. 1,655,395. January 3, 1928 toG. M. Moffett.

The present invention is based on the disl cover),1 that better results are obtained if instead of heating the water, or starch filtrate,

as the case ma be, in a single heater before fine slo system'and at such oint to a relatively Ihigh temperature,- the iiquids entering an'd passing through the system are heated at several places to temperatures which are somewhat lower than ,the initial temperature of the water under the purpose of facilitating ing liquid being tem, by conduit 8. The other solids pass old process. The advantages of this imof heat, a consideration of some importance in a large factory and in a process handling very large quantities of water exposed in thin streams so that radiation losses are high; the avoidance of the danger of excessive heating-at one place; more uniform temperature conditions throughout the fine slop system, wih consequent better separation, the liqui s, successively through the several reels orl shakers of the line slop system being at more nearly the same temperature at all points inv stead of being hotter than necessary at one end of the system and perhaps too cool for efficient operation at the other, and particularly maintenance of the temperatures of the material flowing over the starchtables at the desired elevation without excessive heating at any place in the system in advance of the tables. In this res ect it may be said that in the manufacture ci) starch by the wet method it has been customary to regulate temperatures in the system with respect to desired temperatures at the. table heads, the table headsconstituting one of the principal points lof control for temperature since the maintenance of a proper temperature on 4the tables is essential in order to assure an effective separation between starch and gluten;

The invention is illustrated in a preferred form in the accompanying drawing which is a simplified iow sheet of the entlre starch making invention.

under the improved method, which pass process as'improved by the present Referring to the drawing, the grain is steeped atl with gluten overflow Awater derived from the process, 2 designating the gluten overflow water return pi e in which 1s arranged a heater 3 and a sulp ur tower 4.-. The steep water is drawn of at a and sent to evaporators. The steep i disintegrated in the dismtegrator 5 and is then subjected to a se arating operation at ed grain is coarsely f 6 for the removal of t e germs. The germs are washed at 7, washed germs passing out of the wet starch system at b an the washreturned to the germ sysfrom the germ system by conduit 9 to a grit reel 10, from which the starch and gluten mixture passes through conduit 11 to the starch tables, as will be described, while the ,grits go through conduit 12 to a buhr mill 13, where the material is finely ground. The

ground material passes through conduit 14 to the coarse slop system 15, which consists of a series of reels or shakers that. remove from the magma the coarser particles of bran and fibre, the latter issuing from the wet starch system at c. Gluten overflow water is employed, according to recent practices, for making the separations in the germ sep`' arating and coarse slop systems, 16 indicat- .A ing a pipe leading from the gluten overflow 2O being delivered'by a common conduit 21 to the starch tables 22. The starch settles out on the tables and the bulk of the water with the gluten tails off and is collected in a gluten settler-tank 23, from which leads the gluten overflow Water pipe 2 that supplies the steeping, germ and coarse slop systems with the water necessary for the operations p carried on at these places.

After' the starch has settled on the tables 22, it is flushed off by water derived from the starch washing operation, as will be described, which water is .delivered to the starch tables through pipe 24. The flushed starch passes through a pipe25 to the first of a pair offilters, designated 26 and 27. Here Y the starch lis de-watered and then washed with fresh Water which enters the filter vat 28. The starch from filter 26 passes through conduit 29 to a diluting tank 30 where it is wetup with fresh water, preferably treated with sulphundioxide, which en` ters through pipe 31. The diluted starch passes through conduit 32 to the second filter 27 where it is again dewatered and thereafter washed with fresh Water entering the filter through pipe 33. The filtrate from the second filter, the soluble content of which is low, is used for flushing the starch from the tables, as above described. The ltrate from the first starch filter 26 is first passed through a filter press 34, to remove suspended solids, and is then heated in fthe heater 35.

The system as described so far is the same as that disclosed in the Moffett Patent 1,655,395, above referred to, (to which reference can be made for details not specifi- Vdirect or indirect,l or,

callyillustrated and described herein), except that the starch filtrate from the first filter is not heated to as high a temperature as contemplated in the system of said patent and in thesystem using fresh water for the fine slop which the patented system supplanted. According to the present invention,

the starch filtrate may be heated in heater 35 to a temperature between 100 and 110 F. It enters the fine slo system at substantially this temperature, w 'ch may be increased'if deemed advisable.

The line slop system is shown as consisting of three Washing reels 36, 37, 38, in addition to the draining reel 18, which may perhaps be regarded as part ofthe line slop system. The tailings from the draining reel 18 pass through conduit 39 to the Washing reel 36. The tailings from this reel pass through conduit 40 to washing reel 37 and the tailings` from washing reel 37 pass by conduit 41 to the washing reel 38. process from reel 38, as indicated at d. The starch filtrate heated in the heater 35 passes by pipe 42 to the last Washing reel 38 of the fine slop system. The liquid passing through reel 38 goes through a pipe 43 to washing reel 37. A heater 44 is located in pipe 43. The liquid `passing through reel 37 oes to reel 36 through a pipe 45, 1n which is ocated a heater 46. The heaters 44 and 46 are booster heaters and serve to keep the liquids in the fine slop system substantially up to their` temperature of entrance so 'that the desired table temperatures may be maintained with-- out any excessive heatlng ofthe material at any point in the wet starch system. These heating devices may be of any desired type, the hquids may be heated at these places by the injection of steam. This latter is practicable, if not altogether desirable, since, while the injection of steam introduces a certain amount of water into the system, tending to destroy the Water balance whereby the system operates as a completely closed system, the amount of steam introduced is so small that the increase of water to the system is not a factor ofvery great importance.

Gluten is withdrawn from the system at the gluten outlet e of settler 23. The starch The fine slop leaves the.

which issues at g from the second filter 27 is l finished starch, except as it may require drying if it is to'be marketed as starch. The filter pressing of the filtratev from the first washing filter `26 which takes place in the filter press 34 also yields a certain amount of starch, the outlet for which is indicated at f.

1. In the manufacture of starch from corn by a method. ,v comprising subjecting the starch liquor derived from germ and coarse slop separations to a fine slop separation in a system of sieving devices through which the fine slop mixed with water is passed successively: the improvementv which consists in heating the fine slo liquids at intervals during their passage t rough the flne slop system. c 2. In the manufacture of starch from corn by a method comprising subjecting the starch liquor derived from germ and coarse slop separating operations to a fine lslop separation in a `system of sieving devices through which the fine slop mixed with water is passed successively: the improvement which consists in, heating the Water before it enters the first sieving device of fine slop system and heating the slop and water mixture passing throughy said system in advance of each other sieving' device thereof.4

3. In the manufacture of starch from corn by a method comprising subjecting the starch liquor derived from germ and coarse 2o slop separating operations to a fine slop separation in a system of sieving devices through which the fine slop mixed with water is passed successively, washing the starch, and utilizing the wash water for the ne slop separa-- tion the improvement which consists in heating the Water derived from thestarch washing operation before it enters the first sieving device of the fine slop system and heating the slop and Water mixture passing through the so fine slop system to approximately the same temperature in advance of each of the sieving devices of said system.

FREDERICK` L. JEFFERIES. 

